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diff --git a/clang/lib/StaticAnalyzer/Checkers/ObjCGenericsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/ObjCGenericsChecker.cpp
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+//=== ObjCGenericsChecker.cpp - Path sensitive checker for Generics *- C++ -*=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This checker tries to find type errors that the compiler is not able to catch
+// due to the implicit conversions that were introduced for backward
+// compatibility.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ClangSACheckers.h"
+#include "clang/AST/ParentMap.h"
+#include "clang/AST/RecursiveASTVisitor.h"
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/CheckerManager.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
+
+using namespace clang;
+using namespace ento;
+
+// ProgramState trait - a map from symbol to its specialized type.
+REGISTER_MAP_WITH_PROGRAMSTATE(TypeParamMap, SymbolRef,
+ const ObjCObjectPointerType *)
+
+namespace {
+class ObjCGenericsChecker
+ : public Checker<check::DeadSymbols, check::PreObjCMessage,
+ check::PostObjCMessage, check::PostStmt<CastExpr>> {
+public:
+ ProgramStateRef checkPointerEscape(ProgramStateRef State,
+ const InvalidatedSymbols &Escaped,
+ const CallEvent *Call,
+ PointerEscapeKind Kind) const;
+
+ void checkPreObjCMessage(const ObjCMethodCall &M, CheckerContext &C) const;
+ void checkPostObjCMessage(const ObjCMethodCall &M, CheckerContext &C) const;
+ void checkPostStmt(const CastExpr *CE, CheckerContext &C) const;
+ void checkDeadSymbols(SymbolReaper &SR, CheckerContext &C) const;
+
+private:
+ mutable std::unique_ptr<BugType> BT;
+ void initBugType() const {
+ if (!BT)
+ BT.reset(
+ new BugType(this, "Generics", categories::CoreFoundationObjectiveC));
+ }
+
+ class GenericsBugVisitor : public BugReporterVisitorImpl<GenericsBugVisitor> {
+ public:
+ GenericsBugVisitor(SymbolRef S) : Sym(S) {}
+ ~GenericsBugVisitor() override {}
+
+ void Profile(llvm::FoldingSetNodeID &ID) const override {
+ static int X = 0;
+ ID.AddPointer(&X);
+ ID.AddPointer(Sym);
+ }
+
+ PathDiagnosticPiece *VisitNode(const ExplodedNode *N,
+ const ExplodedNode *PrevN,
+ BugReporterContext &BRC,
+ BugReport &BR) override;
+
+ private:
+ // The tracked symbol.
+ SymbolRef Sym;
+ };
+
+ void reportBug(const ObjCObjectPointerType *From,
+ const ObjCObjectPointerType *To, ExplodedNode *N,
+ SymbolRef Sym, CheckerContext &C,
+ const Stmt *ReportedNode = nullptr) const {
+ initBugType();
+ SmallString<64> Buf;
+ llvm::raw_svector_ostream OS(Buf);
+ OS << "Incompatible pointer types assigning to '";
+ QualType::print(To, Qualifiers(), OS, C.getLangOpts(), llvm::Twine());
+ OS << "' from '";
+ QualType::print(From, Qualifiers(), OS, C.getLangOpts(), llvm::Twine());
+ OS << "'";
+ std::unique_ptr<BugReport> R(new BugReport(*BT, OS.str(), N));
+ R->markInteresting(Sym);
+ R->addVisitor(llvm::make_unique<GenericsBugVisitor>(Sym));
+ if (ReportedNode)
+ R->addRange(ReportedNode->getSourceRange());
+ C.emitReport(std::move(R));
+ }
+};
+} // end anonymous namespace
+
+PathDiagnosticPiece *ObjCGenericsChecker::GenericsBugVisitor::VisitNode(
+ const ExplodedNode *N, const ExplodedNode *PrevN, BugReporterContext &BRC,
+ BugReport &BR) {
+ ProgramStateRef state = N->getState();
+ ProgramStateRef statePrev = PrevN->getState();
+
+ const ObjCObjectPointerType *const *TrackedType =
+ state->get<TypeParamMap>(Sym);
+ const ObjCObjectPointerType *const *TrackedTypePrev =
+ statePrev->get<TypeParamMap>(Sym);
+ if (!TrackedType)
+ return nullptr;
+
+ if (TrackedTypePrev && *TrackedTypePrev == *TrackedType)
+ return nullptr;
+
+ // Retrieve the associated statement.
+ const Stmt *S = nullptr;
+ ProgramPoint ProgLoc = N->getLocation();
+ if (Optional<StmtPoint> SP = ProgLoc.getAs<StmtPoint>()) {
+ S = SP->getStmt();
+ }
+
+ if (!S)
+ return nullptr;
+
+ const LangOptions &LangOpts = BRC.getASTContext().getLangOpts();
+
+ SmallString<64> Buf;
+ llvm::raw_svector_ostream OS(Buf);
+ OS << "Type '";
+ QualType::print(*TrackedType, Qualifiers(), OS, LangOpts, llvm::Twine());
+ OS << "' is infered from ";
+
+ if (const auto *ExplicitCast = dyn_cast<ExplicitCastExpr>(S)) {
+ OS << "explicit cast (from '";
+ QualType::print(ExplicitCast->getSubExpr()->getType().getTypePtr(),
+ Qualifiers(), OS, LangOpts, llvm::Twine());
+ OS << "' to '";
+ QualType::print(ExplicitCast->getType().getTypePtr(), Qualifiers(), OS,
+ LangOpts, llvm::Twine());
+ OS << "')";
+ } else if (const auto *ImplicitCast = dyn_cast<ImplicitCastExpr>(S)) {
+ OS << "implicit cast (from '";
+ QualType::print(ImplicitCast->getSubExpr()->getType().getTypePtr(),
+ Qualifiers(), OS, LangOpts, llvm::Twine());
+ OS << "' to '";
+ QualType::print(ImplicitCast->getType().getTypePtr(), Qualifiers(), OS,
+ LangOpts, llvm::Twine());
+ OS << "')";
+ } else {
+ OS << "this context";
+ }
+
+ // Generate the extra diagnostic.
+ PathDiagnosticLocation Pos(S, BRC.getSourceManager(),
+ N->getLocationContext());
+ return new PathDiagnosticEventPiece(Pos, OS.str(), true, nullptr);
+}
+
+void ObjCGenericsChecker::checkDeadSymbols(SymbolReaper &SR,
+ CheckerContext &C) const {
+ if (!SR.hasDeadSymbols())
+ return;
+
+ ProgramStateRef State = C.getState();
+ TypeParamMapTy TyParMap = State->get<TypeParamMap>();
+ for (TypeParamMapTy::iterator I = TyParMap.begin(), E = TyParMap.end();
+ I != E; ++I) {
+ if (SR.isDead(I->first)) {
+ State = State->remove<TypeParamMap>(I->first);
+ }
+ }
+}
+
+static const ObjCObjectPointerType *getMostInformativeDerivedClassImpl(
+ const ObjCObjectPointerType *From, const ObjCObjectPointerType *To,
+ const ObjCObjectPointerType *MostInformativeCandidate, ASTContext &C) {
+ // Checking if from and to are the same classes modulo specialization.
+ if (From->getInterfaceDecl()->getCanonicalDecl() ==
+ To->getInterfaceDecl()->getCanonicalDecl()) {
+ if (To->isSpecialized()) {
+ assert(MostInformativeCandidate->isSpecialized());
+ return MostInformativeCandidate;
+ }
+ return From;
+ }
+ const auto *SuperOfTo =
+ To->getObjectType()->getSuperClassType()->getAs<ObjCObjectType>();
+ assert(SuperOfTo);
+ QualType SuperPtrOfToQual =
+ C.getObjCObjectPointerType(QualType(SuperOfTo, 0));
+ const auto *SuperPtrOfTo = SuperPtrOfToQual->getAs<ObjCObjectPointerType>();
+ if (To->isUnspecialized())
+ return getMostInformativeDerivedClassImpl(From, SuperPtrOfTo, SuperPtrOfTo,
+ C);
+ else
+ return getMostInformativeDerivedClassImpl(From, SuperPtrOfTo,
+ MostInformativeCandidate, C);
+}
+
+/// Get the most derived class if From that do not loose information about type
+/// parameters. To has to be a subclass of From. From has to be specialized.
+static const ObjCObjectPointerType *
+getMostInformativeDerivedClass(const ObjCObjectPointerType *From,
+ const ObjCObjectPointerType *To, ASTContext &C) {
+ return getMostInformativeDerivedClassImpl(From, To, To, C);
+}
+
+static bool storeWhenMoreInformative(ProgramStateRef &State, SymbolRef Sym,
+ const ObjCObjectPointerType *const *Old,
+ const ObjCObjectPointerType *New,
+ ASTContext &C) {
+ if (!Old || C.canAssignObjCInterfaces(*Old, New)) {
+ State = State->set<TypeParamMap>(Sym, New);
+ return true;
+ }
+ return false;
+}
+
+void ObjCGenericsChecker::checkPostStmt(const CastExpr *CE,
+ CheckerContext &C) const {
+ if (CE->getCastKind() != CK_BitCast)
+ return;
+
+ QualType OriginType = CE->getSubExpr()->getType();
+ QualType DestType = CE->getType();
+
+ const auto *OrigObjectPtrType = OriginType->getAs<ObjCObjectPointerType>();
+ const auto *DestObjectPtrType = DestType->getAs<ObjCObjectPointerType>();
+
+ if (!OrigObjectPtrType || !DestObjectPtrType)
+ return;
+
+ ASTContext &ASTCtxt = C.getASTContext();
+
+ // This checker detects the subtyping relationships using the assignment
+ // rules. In order to be able to do this the kindofness must be stripped
+ // first. The checker treats every type as kindof type anyways: when the
+ // tracked type is the subtype of the static type it tries to look up the
+ // methods in the tracked type first.
+ OrigObjectPtrType = OrigObjectPtrType->stripObjCKindOfTypeAndQuals(ASTCtxt);
+ DestObjectPtrType = DestObjectPtrType->stripObjCKindOfTypeAndQuals(ASTCtxt);
+
+ const ObjCObjectType *OrigObjectType = OrigObjectPtrType->getObjectType();
+ const ObjCObjectType *DestObjectType = DestObjectPtrType->getObjectType();
+
+ if (OrigObjectType->isUnspecialized() && DestObjectType->isUnspecialized())
+ return;
+
+ ProgramStateRef State = C.getState();
+ SymbolRef Sym = State->getSVal(CE, C.getLocationContext()).getAsSymbol();
+ if (!Sym)
+ return;
+
+ // Check which assignments are legal.
+ bool OrigToDest =
+ ASTCtxt.canAssignObjCInterfaces(DestObjectPtrType, OrigObjectPtrType);
+ bool DestToOrig =
+ ASTCtxt.canAssignObjCInterfaces(OrigObjectPtrType, DestObjectPtrType);
+ const ObjCObjectPointerType *const *TrackedType =
+ State->get<TypeParamMap>(Sym);
+
+ // If OrigObjectType could convert to DestObjectType, this could be an
+ // implicit cast. Do not treat that cast as explicit in that case.
+ if (isa<ExplicitCastExpr>(CE) && !OrigToDest) {
+ if (DestToOrig) {
+ // Trust explicit downcasts.
+ // However a downcast may also lose information. E. g.:
+ // MutableMap<T, U> : Map
+ // The downcast to MutableMap loses the information about the types of the
+ // Map (due to the type parameters are not being forwarded to Map), and in
+ // general there is no way to recover that information from the
+ // declaration. In order to have to most information, lets find the most
+ // derived type that has all the type parameters forwarded.
+ const ObjCObjectPointerType *WithMostInfo =
+ getMostInformativeDerivedClass(OrigObjectPtrType, DestObjectPtrType,
+ C.getASTContext());
+ if (storeWhenMoreInformative(State, Sym, TrackedType, WithMostInfo,
+ ASTCtxt))
+ C.addTransition(State);
+ return;
+ }
+ // Mismatched types. If the DestType specialized, store it. Forget the
+ // tracked type otherwise.
+ if (DestObjectPtrType->isSpecialized()) {
+ State = State->set<TypeParamMap>(Sym, DestObjectPtrType);
+ C.addTransition(State);
+ } else if (TrackedType) {
+ State = State->remove<TypeParamMap>(Sym);
+ C.addTransition(State);
+ }
+ return;
+ }
+
+ // Handle implicit casts and explicit upcasts.
+
+ if (DestObjectType->isUnspecialized()) {
+ assert(OrigObjectType->isSpecialized());
+ // In case we already have some type information for this symbol from a
+ // Specialized -> Specialized conversion, do not record the OrigType,
+ // because it might contain less type information than the tracked type.
+ if (!TrackedType) {
+ State = State->set<TypeParamMap>(Sym, OrigObjectPtrType);
+ C.addTransition(State);
+ }
+ return;
+ }
+
+ // The destination type is specialized.
+
+ // The tracked type should be the sub or super class of the static destination
+ // type. When an (implicit) upcast or a downcast happens according to static
+ // types, and there is no subtyping relationship between the tracked and the
+ // static destination types, it indicates an error.
+ if (TrackedType &&
+ !ASTCtxt.canAssignObjCInterfaces(DestObjectPtrType, *TrackedType) &&
+ !ASTCtxt.canAssignObjCInterfaces(*TrackedType, DestObjectPtrType)) {
+ static CheckerProgramPointTag IllegalConv(this, "IllegalConversion");
+ ExplodedNode *N = C.addTransition(State, C.getPredecessor(), &IllegalConv);
+ reportBug(*TrackedType, DestObjectPtrType, N, Sym, C);
+ return;
+ }
+
+ if (OrigToDest && !DestToOrig) {
+ // When upcast happens, store the type with the most information about the
+ // type parameters.
+ const ObjCObjectPointerType *WithMostInfo = getMostInformativeDerivedClass(
+ DestObjectPtrType, OrigObjectPtrType, ASTCtxt);
+ if (storeWhenMoreInformative(State, Sym, TrackedType, WithMostInfo,
+ ASTCtxt))
+ C.addTransition(State);
+ return;
+ }
+
+ // Downcast happens.
+
+ // Trust tracked type on unspecialized value -> specialized implicit
+ // downcasts.
+ if (storeWhenMoreInformative(State, Sym, TrackedType, DestObjectPtrType,
+ ASTCtxt)) {
+ C.addTransition(State);
+ }
+}
+
+static const Expr *stripCastsAndSugar(const Expr *E) {
+ E = E->IgnoreParenImpCasts();
+ if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E))
+ E = POE->getSyntacticForm()->IgnoreParenImpCasts();
+ if (const OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E))
+ E = OVE->getSourceExpr()->IgnoreParenImpCasts();
+ return E;
+}
+
+// This callback is used to infer the types for Class variables. This info is
+// used later to validate messages that sent to classes. Class variables are
+// initialized with by invoking the 'class' method on a class.
+void ObjCGenericsChecker::checkPostObjCMessage(const ObjCMethodCall &M,
+ CheckerContext &C) const {
+ const ObjCMessageExpr *MessageExpr = M.getOriginExpr();
+
+ SymbolRef Sym = M.getReturnValue().getAsSymbol();
+ if (!Sym)
+ return;
+
+ Selector Sel = MessageExpr->getSelector();
+ // We are only interested in cases where the class method is invoked on a
+ // class. This method is provided by the runtime and available on all classes.
+ if (MessageExpr->getReceiverKind() != ObjCMessageExpr::Class ||
+ Sel.getAsString() != "class")
+ return;
+
+ QualType ReceiverType = MessageExpr->getClassReceiver();
+ const auto *ReceiverClassType = ReceiverType->getAs<ObjCObjectType>();
+ QualType ReceiverClassPointerType =
+ C.getASTContext().getObjCObjectPointerType(
+ QualType(ReceiverClassType, 0));
+
+ if (!ReceiverClassType->isSpecialized())
+ return;
+ const auto *InferredType =
+ ReceiverClassPointerType->getAs<ObjCObjectPointerType>();
+ assert(InferredType);
+
+ ProgramStateRef State = C.getState();
+ State = State->set<TypeParamMap>(Sym, InferredType);
+ C.addTransition(State);
+}
+
+static bool isObjCTypeParamDependent(QualType Type) {
+ // It is illegal to typedef parameterized types inside an interface. Therfore
+ // an
+ // Objective-C type can only be dependent on a type parameter when the type
+ // parameter structurally present in the type itself.
+ class IsObjCTypeParamDependentTypeVisitor
+ : public RecursiveASTVisitor<IsObjCTypeParamDependentTypeVisitor> {
+ public:
+ IsObjCTypeParamDependentTypeVisitor() : Result(false) {}
+ bool VisitTypedefType(const TypedefType *Type) {
+ if (isa<ObjCTypeParamDecl>(Type->getDecl())) {
+ Result = true;
+ return false;
+ }
+ return true;
+ }
+ bool getResult() { return Result; }
+
+ private:
+ bool Result;
+ };
+
+ IsObjCTypeParamDependentTypeVisitor Visitor;
+ Visitor.TraverseType(Type);
+ return Visitor.getResult();
+}
+
+// A method might not be available in the interface indicated by the static
+// type. However it might be available in the tracked type. In order to properly
+// substitute the type parameters we need the declaration context of the method.
+// The more specialized the enclosing class of the method is, the more likely
+// that the parameter substitution will be successful.
+static const ObjCMethodDecl *
+findMethodDecl(const ObjCMessageExpr *MessageExpr,
+ const ObjCObjectPointerType *TrackedType, ASTContext &ASTCtxt) {
+ const ObjCMethodDecl *Method = nullptr;
+
+ QualType ReceiverType = MessageExpr->getReceiverType();
+ const auto *ReceiverObjectPtrType =
+ ReceiverType->getAs<ObjCObjectPointerType>();
+
+ // Do this "devirtualization" on instance and class methods only. Trust the
+ // static type on super and super class calls.
+ if (MessageExpr->getReceiverKind() == ObjCMessageExpr::Instance ||
+ MessageExpr->getReceiverKind() == ObjCMessageExpr::Class) {
+ // When the receiver type is id, Class, or some super class of the tracked
+ // type, look up the method in the tracked type, not in the receiver type.
+ // This way we preserve more information.
+ if (ReceiverType->isObjCIdType() || ReceiverType->isObjCClassType() ||
+ ASTCtxt.canAssignObjCInterfaces(ReceiverObjectPtrType, TrackedType)) {
+ const ObjCInterfaceDecl *InterfaceDecl = TrackedType->getInterfaceDecl();
+ // The method might not be found.
+ Selector Sel = MessageExpr->getSelector();
+ Method = InterfaceDecl->lookupInstanceMethod(Sel);
+ if (!Method)
+ Method = InterfaceDecl->lookupClassMethod(Sel);
+ }
+ }
+
+ // Fallback to statick method lookup when the one based on the tracked type
+ // failed.
+ return Method ? Method : MessageExpr->getMethodDecl();
+}
+
+// When the receiver has a tracked type, use that type to validate the
+// argumments of the message expression and the return value.
+void ObjCGenericsChecker::checkPreObjCMessage(const ObjCMethodCall &M,
+ CheckerContext &C) const {
+ ProgramStateRef State = C.getState();
+ SymbolRef Sym = M.getReceiverSVal().getAsSymbol();
+ if (!Sym)
+ return;
+
+ const ObjCObjectPointerType *const *TrackedType =
+ State->get<TypeParamMap>(Sym);
+ if (!TrackedType)
+ return;
+
+ // Get the type arguments from tracked type and substitute type arguments
+ // before do the semantic check.
+
+ ASTContext &ASTCtxt = C.getASTContext();
+ const ObjCMessageExpr *MessageExpr = M.getOriginExpr();
+ const ObjCMethodDecl *Method =
+ findMethodDecl(MessageExpr, *TrackedType, ASTCtxt);
+
+ // It is possible to call non-existent methods in Obj-C.
+ if (!Method)
+ return;
+
+ Optional<ArrayRef<QualType>> TypeArgs =
+ (*TrackedType)->getObjCSubstitutions(Method->getDeclContext());
+ // This case might happen when there is an unspecialized override of a
+ // specialized method.
+ if (!TypeArgs)
+ return;
+
+ for (unsigned i = 0; i < Method->param_size(); i++) {
+ const Expr *Arg = MessageExpr->getArg(i);
+ const ParmVarDecl *Param = Method->parameters()[i];
+
+ QualType OrigParamType = Param->getType();
+ if (!isObjCTypeParamDependent(OrigParamType))
+ continue;
+
+ QualType ParamType = OrigParamType.substObjCTypeArgs(
+ ASTCtxt, *TypeArgs, ObjCSubstitutionContext::Parameter);
+ // Check if it can be assigned
+ const auto *ParamObjectPtrType = ParamType->getAs<ObjCObjectPointerType>();
+ const auto *ArgObjectPtrType =
+ stripCastsAndSugar(Arg)->getType()->getAs<ObjCObjectPointerType>();
+ if (!ParamObjectPtrType || !ArgObjectPtrType)
+ continue;
+
+ // Check if we have more concrete tracked type that is not a super type of
+ // the static argument type.
+ SVal ArgSVal = M.getArgSVal(i);
+ SymbolRef ArgSym = ArgSVal.getAsSymbol();
+ if (ArgSym) {
+ const ObjCObjectPointerType *const *TrackedArgType =
+ State->get<TypeParamMap>(ArgSym);
+ if (TrackedArgType &&
+ ASTCtxt.canAssignObjCInterfaces(ArgObjectPtrType, *TrackedArgType)) {
+ ArgObjectPtrType = *TrackedArgType;
+ }
+ }
+
+ // Warn when argument is incompatible with the parameter.
+ if (!ASTCtxt.canAssignObjCInterfaces(ParamObjectPtrType,
+ ArgObjectPtrType)) {
+ static CheckerProgramPointTag Tag(this, "ArgTypeMismatch");
+ ExplodedNode *N = C.addTransition(State, C.getPredecessor(), &Tag);
+ reportBug(ArgObjectPtrType, ParamObjectPtrType, N, Sym, C, Arg);
+ return;
+ }
+ }
+ QualType StaticResultType = Method->getReturnType();
+ // Check whether the result type was a type parameter.
+ bool IsDeclaredAsInstanceType =
+ StaticResultType == ASTCtxt.getObjCInstanceType();
+ if (!isObjCTypeParamDependent(StaticResultType) && !IsDeclaredAsInstanceType)
+ return;
+
+ QualType ResultType = Method->getReturnType().substObjCTypeArgs(
+ ASTCtxt, *TypeArgs, ObjCSubstitutionContext::Result);
+ if (IsDeclaredAsInstanceType)
+ ResultType = QualType(*TrackedType, 0);
+
+ const Stmt *Parent =
+ C.getCurrentAnalysisDeclContext()->getParentMap().getParent(MessageExpr);
+ if (M.getMessageKind() != OCM_Message) {
+ // Properties and subscripts are not direct parents.
+ Parent =
+ C.getCurrentAnalysisDeclContext()->getParentMap().getParent(Parent);
+ }
+
+ const auto *ImplicitCast = dyn_cast_or_null<ImplicitCastExpr>(Parent);
+ if (!ImplicitCast || ImplicitCast->getCastKind() != CK_BitCast)
+ return;
+
+ const auto *ExprTypeAboveCast =
+ ImplicitCast->getType()->getAs<ObjCObjectPointerType>();
+ const auto *ResultPtrType = ResultType->getAs<ObjCObjectPointerType>();
+
+ if (!ExprTypeAboveCast || !ResultPtrType)
+ return;
+
+ // Only warn on unrelated types to avoid too many false positives on
+ // downcasts.
+ if (!ASTCtxt.canAssignObjCInterfaces(ExprTypeAboveCast, ResultPtrType) &&
+ !ASTCtxt.canAssignObjCInterfaces(ResultPtrType, ExprTypeAboveCast)) {
+ static CheckerProgramPointTag Tag(this, "ReturnTypeMismatch");
+ ExplodedNode *N = C.addTransition(State, C.getPredecessor(), &Tag);
+ reportBug(ResultPtrType, ExprTypeAboveCast, N, Sym, C);
+ return;
+ }
+}
+
+/// Register checker.
+void ento::registerObjCGenericsChecker(CheckerManager &mgr) {
+ mgr.registerChecker<ObjCGenericsChecker>();
+}
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